| title | ISBN-13 (ISBN-10) | year of publica- tion | other author(s) |
|---|---|---|---|
| English and Celtic in contact | 978-0-203-89500-9 (0-203-89500-2) | 2008 | Markku Filppula · Juhani Klemola · |
| Vernacular Universals and Language Contacts: Evidence from Varieties of English and Beyond | 978-0-415-99239-8 (0-415-99239-7) | 2009 | Markku Filppula · Juhani Klemola |
| Welsh English | 978-1-61451-381-0 (1-61451-381-3) | 2020 | Rob Penhallurick |